197,046 research outputs found
Optimum energy partition between data and midamble for channel estimation in TD-CDMA
No full textChannel estimation in the uplink of a TD-CDTMA system can be accomplished by inserting 11 known sequence of symbols at the chip rate, usually in the middle of the burst, and therefore called midamble. In this paper we found the analytical solution to the problem of optimum energy partition, given the total energy per burst, between the midamble and data fields, in joint detected TD-CDMA systems. We show that, given the lengths of the data and midamble, in general the optimal solution requires different amplitude levels. We also show the burst structure in order to reach the optimum energy partition with equal amplitude symbols, and the performance degradation with traditional choices. The analysis is validated, for different channels, by comparison with simulation results of the TD-CDMA radio interlace specified for third generation cellular systems, where gains in terms of signal-to-noise ratio of 0.5-0.9 dB are achieveable
Bartonella henselae adhesin A (BadA), a novel non-fimbrial adhesin mediating a proangiogenic host cell response
No full textBartonella henselae causes vasculoproliferative disorders in humans. We identified a novel non-fimbrial adhesin of B. henselae designated as B. henselae adhesin A (BadA). BadA is a 340 kD protein encoded by the 9.3 kb badA gene and located in the outer membrane of B. henselae. BadA has a modular structure and contains domains homologous to Yersinia enterocolitica YadA. Expression of BadA was restored in a BadA-deficient transposon mutant by complementation in trans as shown by electronmicroscopy. BadA mediates the binding of B. henselae to extracellular matrix proteins and to endothelial cells. Expression of BadA is crucial for activation of hypoxia-inducible factor-1 (HIF-1) in host cells by B. henselae and secretion of proangiogenic cytokines (e.g., vascular endothelial growth factor). BadA is immunodominant in B. henselae-infected patients and rodents indicating that it is expressed during Bartonella infections. Our results suggest that BadA, the largest so far characterized bacterial protein, is a major pathogenicity factor of B. henselae with a role in the induction of vasculoproliferative disorders
Arrival and departure manager cooperation for reducing airborne holding times at destination airports
No full textThis thesis addresses the possibility of using a delay-on-ground concept in which flights with less than 1 hour flying time (often referred to as pop-up flights) absorb their arrival sequencing delay at the departure gate by being issued their Arrival Manager (AMAN)-scheduled time as a Required Time of Arrival (RTA) that is inserted into the Flight Management System (FMS). Due to their short duration these flights are currently often inserted into the AMAN sequence shortly before Terminal Manoeuvring Area (TMA) entry and thereby often need to absorb their arrival sequencing delay in the inefficient manner of airborne holding or vectoring close to the arrival airport. The literature review examines current operational procedures of AMANs and Departure Managers (DMANs), the current FMS RTA function and live trials in which the delay-on-ground concept was tested in real operations. A case study airport in Europe that has potential to benefit from the concept is identified. The performance of the delay-on-ground concept for the case study airport is then assessed by performing 180 fast-time Monte Carlo simulation runs. For each run the arrival flow to the case study airport and the departure flows from two medium-sized airports from which the pop-up flights originate are simulated. Each run represents an operational day and variations in departure/arrivals time is put into the timetables to simulate the variation in actual departure/arrival times resulting from operational factors normally encountered in day-to-day operations. An algorithm is written in Matlab to simulate an AMAN-DMAN cooperation in which pop-up flights are locked to the required departure times to meet their RTAs. It is shown that a significant reduction in airborne delay time and fuel consumption can be achieved at the case study airport by using the concept. It is also shown that it is possible to ensure that the pop-up flights depart at the required times to meet their RTAs without negatively affecting the departure sequences
Bartonella henselae trimeric autotransporter adhesin BadA expression interferes with effector translocation by the VirB/D4 type IV secretion system
No full textThe gram-negative, zoonotic pathogen Bartonella henselae is the aetiologic agent of cat scratch disease, bacillary angiomatosis and peliosis hepatis in humans. Two pathogenicity factors of B. henselae - each displaying multiple functions in host cell interaction - have been characterized in greater detail: the trimeric autotransporter Bartonella adhesin A (BadA) and the type IV secretion system VirB/D4 (VirB/D4 T4SS). BadA mediates, e.g., binding to fibronectin (Fn), adherence to endothelial cells (ECs) and secretion of vascular endothelial growth factor (VEGF). VirB/D4 translocates several Bartonella effector proteins (Beps) into the cytoplasm of infected ECs, resulting, e.g., in uptake of bacterial aggregates via the invasome structure, inhibition of apoptosis and activation of a proangiogenic phenotype. Despite this knowledge of the individual activities of BadA or VirB/D4 it is unknown whether these major virulence factors affect each other in their specific activities. In this study, expression and function of BadA and VirB/D4 were analyzed in a variety of clinical B. henselae isolates. Data revealed that most isolates have lost expression of either BadA or VirB/D4 during in vitro passages. However, the phenotypic effects of co-expression of both virulence factors was studied in one clinical isolate that was found to stably co-express BadA and VirB/D4, as well as by ectopic expression of BadA in a strain expressing VirB/D4 but not BadA. BadA, which forms a dense layer on the bacterial surface, negatively affected VirB/D4-dependent Bep translocation and invasome formation by likely preventing close contact between the bacterial cell envelope and the host cell membrane. In contrast, BadA-dependent Fn binding, adhesion to ECs and VEGF secretion were not affected by a functional VirB/D4 T4SS. The obtained data imply that the essential virulence factors BadA and VirB/D4 are likely differentially expressed during different stages of the infection cycle of Bartonella
DETERMINASI LAPISAN TERINTRUSI AIR LAUT DENGAN METODE RESISTIVITAS DI KAWASAN PEUKAN BADA, ACEH BESAR
No full textABSTRAKTelah dilakukan penelitian dengan menggunakan metode resistivitas konfigurasi pole-dipole di Kecamatan Peukan Bada, Aceh Besar. Penelitian ini bertujuan untuk mengetahui variasi nilai resistivitas lapisan bawah permukaan yang berpotensi terintrusi air laut di Desa Baro, Lam Manyang, dan Lam Teeh. Akuisisi data dilakukan pada 3 lintasan pengukuran dengan panjang masing-masing lintasan 200 m dan jarak antar elektroda 5 m. Pemrosesan data hasil akuisisi menggunakan Software Res2Dinv untuk mendapatkan penampang 2D lapisan bawah permukaan. Hasil pengolahan data dari ke 3 lintasan menunjukan bahwa nilai resistivitas untuk lapisan terintrusi air laut pada daerah penelitian adalah -10 sampai 47 ?m dengan kedalaman bervariasi, yaitu 1 sampai 62 m. Struktur bawah permukaan di daerah tersebut terdiri dari alluvium berupa pasir, kerikil, dan lumpur. Berdasarkan hasil interpretasi data dapat disimpulkan bahwa penyebaran intrusi air laut terdapat pada semua lintasan pengukuran di lokasi penelitian. Hasil penelitian menunjukkan bahwa metode resistivitas dapat digunakan untuk mengidentifikasi lapisan bawah permukaan yang terintrusi air laut di Kawasan Peukan Bada, Aceh Besar.Kata kunci-: Metode geolistrik, konfigurasi pole-dipole, nilai resistivitas, lapisan terintrusi air laut, Kecamatan Peukan Bada
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Dr. Glendon Swarthout
No full textHosted by Roger M. Busfield, MSU Assistant Professor of Speech and Theater, Meet the Author is designed to introduce a general audience to a contemporary author and their work through in-depth interviews. This episode features a conversation between Dr. Glendon Swarthout, prolific author and English professor at MSU, and assistant professors Sam S. Baskett and Theodore B. Strandness
Supersonic Diversions: Assessment of Great-Circle versus Sonic Boom-Restricted Flight Routing
No full textOverland supersonic flight bans due to the sonic boom are often said to be the reason for civil high-speed aircraft not being able to make a breakthrough. However, there is an apparent lack of studies actually quantifying the disadvantage of law-compliant supersonic flight paths versus optimum overland tracks. This paper presents a framework of city pair-specific flight routes and mission performance simulation for accurate operational assessment of supersonic airplane designs. By application to a supposedly realistic representation of a future civil supersonic air transportation system as a use-case, the impact of rerouting on flight distance, block times, and block fuels is quantified locally as well as globally
- …
